This invention relates in general to gaseous fuel systems for engines. Engines are used in a variety of vehicles and equipment. Most commercially available engines use either liquid or gaseous fuel as their fuel source. For example, it is well known to use gasoline or diesel as a fuel source for engines in various vehicles and equipment such as lawn mowers, compressors, generators, blowers, etc. It is also known to use gaseous fuels, such as propane, liquefied petroleum gas, natural gas, and hydrogen as fuel sources for engines. Some engines are also configured as dual fuel engines, wherein either or liquid fuel or a gaseous fuel can be used as the fuel source to a single engine. There also kits commercially available for converting an engine that was originally designed and manufactured for using gasoline or diesel as fuel sources to using gaseous fuels instead. Some advantages of using gaseous fuels, such as propane, instead of liquid fuels, such as gasoline or diesel, include lower fuel costs per operating hour, higher octane ratings, increased engine life and lower maintenance cost due to the gaseous fuel burning cleaner compared to some liquid fuels. Additionally, propane reduces hydrocarbon emissions and has less environmental impact compared to gasoline and diesel engines.
Engines using gaseous fuels include a fuel delivery system. These systems can be built integrally with the engines or can be installed in a kit-type of configuration used to convert an engine originally designed for using gasoline or diesel as fuel sources to using gaseous fuels instead. Conventionally known gaseous fuel delivery systems commonly include a regulator valve for reducing the generally high pressure level and flow rate from a source of gaseous fuel (tank) to a lower pressure and/or flow rate for proper fuel intake in the corresponding engine. A fuel control valve is also provided in the gaseous fuel delivery system to control the flow of propane between the tank and the engine. It is known to use valves that are manually operated or controlled by electronic, pneumatic, or hydraulic sources.